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Diffstat (limited to 'ipc/chromium/src/base/waitable_event_win.cc')
-rw-r--r--ipc/chromium/src/base/waitable_event_win.cc88
1 files changed, 88 insertions, 0 deletions
diff --git a/ipc/chromium/src/base/waitable_event_win.cc b/ipc/chromium/src/base/waitable_event_win.cc
new file mode 100644
index 000000000..77a1f2056
--- /dev/null
+++ b/ipc/chromium/src/base/waitable_event_win.cc
@@ -0,0 +1,88 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/waitable_event.h"
+
+#include <math.h>
+#include <windows.h>
+
+#include "base/logging.h"
+#include "base/time.h"
+
+namespace base {
+
+WaitableEvent::WaitableEvent(bool manual_reset, bool signaled)
+ : handle_(CreateEvent(NULL, manual_reset, signaled, NULL)) {
+ // We're probably going to crash anyways if this is ever NULL, so we might as
+ // well make our stack reports more informative by crashing here.
+ CHECK(handle_);
+}
+
+WaitableEvent::~WaitableEvent() {
+ CloseHandle(handle_);
+}
+
+void WaitableEvent::Reset() {
+ ResetEvent(handle_);
+}
+
+void WaitableEvent::Signal() {
+ SetEvent(handle_);
+}
+
+bool WaitableEvent::IsSignaled() {
+ return TimedWait(TimeDelta::FromMilliseconds(0));
+}
+
+bool WaitableEvent::Wait() {
+ DWORD result = WaitForSingleObject(handle_, INFINITE);
+ // It is most unexpected that this should ever fail. Help consumers learn
+ // about it if it should ever fail.
+ DCHECK(result == WAIT_OBJECT_0) << "WaitForSingleObject failed";
+ return result == WAIT_OBJECT_0;
+}
+
+bool WaitableEvent::TimedWait(const TimeDelta& max_time) {
+ DCHECK(max_time >= TimeDelta::FromMicroseconds(0));
+ // Be careful here. TimeDelta has a precision of microseconds, but this API
+ // is in milliseconds. If there are 5.5ms left, should the delay be 5 or 6?
+ // It should be 6 to avoid returning too early.
+ double timeout = ceil(max_time.InMillisecondsF());
+ DWORD result = WaitForSingleObject(handle_, static_cast<DWORD>(timeout));
+ switch (result) {
+ case WAIT_OBJECT_0:
+ return true;
+ case WAIT_TIMEOUT:
+ return false;
+ }
+ // It is most unexpected that this should ever fail. Help consumers learn
+ // about it if it should ever fail.
+ NOTREACHED() << "WaitForSingleObject failed";
+ return false;
+}
+
+// static
+size_t WaitableEvent::WaitMany(WaitableEvent** events, size_t count) {
+ HANDLE handles[MAXIMUM_WAIT_OBJECTS];
+ CHECK(count <= MAXIMUM_WAIT_OBJECTS)
+ << "Can only wait on " << MAXIMUM_WAIT_OBJECTS << " with WaitMany";
+
+ for (size_t i = 0; i < count; ++i)
+ handles[i] = events[i]->handle();
+
+ DWORD result =
+ WaitForMultipleObjects(count, handles,
+ FALSE, // don't wait for all the objects
+ INFINITE); // no timeout
+ if (result >= WAIT_OBJECT_0 + count) {
+ NOTREACHED() << "WaitForMultipleObjects failed: " << GetLastError();
+ return 0;
+ }
+
+ return result - WAIT_OBJECT_0;
+}
+
+} // namespace base